1. Field of Invention
This invention relates to methods and systems for routing queries and responses within an ad hoc network.
2. Description of Related Art
Networked sensors are widely used in various applications. For example, tiny inexpensive sensors can be distributed onto, or installed within, roads, walls, or machines to monitor and detect a variety of interesting events, such as highway traffic, wildlife habitat conditions, forest fires, materials and/or process flows in manufacturing jobs, and military battlefield situations.
Because of the spatial coverage and of the multiplicity in sensing aspect and modality that distributed sensors can provide, a sensor network is ideally suited for checking moving phenomena, such as moving vehicles or people, that traverse the range of many sensors in a large area, for monitoring a large number of objects or events simultaneously, such as, for example, forest fires or large animal herds, and/or for detecting low-observable events, such as stealthy, low-signal-to-noise-ratio sources, that may be subject to loud distracters or other counter-measures.
Detecting, classifying and tracking moving non-local, low-observable events require non-local collaboration among sensors of a sensor network. Aggregating sensor data from a multitude of sensors can improve accuracy. However, the data bandwidth and power available to individual sensors in a sensor network is typically constrained. Informed selective collaboration of sensors, in contrast to flooding data requests to all sensors, can reduce latency. Moreover, sensor collaboration can minimize bandwidth consumption, which leads to energy savings, and which mitigates the effect of network node/link failures. Because most inexpensive, distributed sensors are untethered and battery-powered, the longevity of a network depends on the rate the power is consumed when performing computation and communication tasks.